Rotary fan.



wn CARRIER. ROTARY FAN.

AFPLICATWN FILED SEPT. 20. 191 l.

Patented May 4, 1915.

2 SHEETS-SHEET I.

Mfrz e 6660:-

W. H. CARRIER.

ROTARY FAN. APPLICATION man SEPT.20. 19H.

Patented May 1915.

2 SHEETS-SHEET 2 KRQ A R jz zorrzega.

WILLIS H. CARRIER, OF BUFFALO,

NEW YORK, ASST I NOR TO BUFFALO FORGE COMPANY, OF BUFFALO, NEW YORK.

ROTARY FAN.

Application filed September 20, 1911.

To all whom it may concern:

Be it known that I, WILLIs H. CARRIER, a citizen of the United States, residingat Buffalo, in the county of Erie and State of New York, have invented a new and useful Improvement in Rotary Fans, of which the following is a specification.

This invention relates to multivane rotary centrifugal fans of that kind which have a large number of blades or vanes which are arranged relatively close together in an annular series around a central space which is open at one side for the entrance of the air which passes outwardly between the blades and in which the blades are made relatively long in a radial direction to 1mpart to the air the maximum amount of centrifugal force.

The objects of this invention are to provide a fan of this kind with blades or vanes which are so shaped and arranged that the shock caused by the impact between air and the rotating blades is reduced to a minimum, and the air is discharged uniformly with substantially the same velocity and pressure throughout the width of the blade, thereby producing a fan of the maximum efliciency; also to enable the use of fan blades which are developable from a conical surface to facilitate the manufacture and decrease the cost of making the blades and insure an even surface along which the fluid can flow with the minimum resistance.

The fan is primarily intended for pelling air, andin this specification term air is employed to designate fluid acted upon by the fan, but it is not tended thereby to restrict the use of the fan, which is also adapted for use with other gases or fluids.

in the accompanying drawings, consisting of two sheets: Figure 1 is a sectional elevation on line 1-1, Fig. 2, of a fan embodying the invention. Fig. 2 is a transverse sectional elevation on line 22, Fig. 1. Figs. 3 and at are respectively an end view and a face view of one of the fan blades, and showing by dotted lines the conical surface from which the blade is developed. Fig. 5 is anelevation of removed from the casing.

Like reference characters refer to like parts in the several figures.

A represents the casing of has an air inlet or eye a at prothe the inthe fan which one side and a Specification of Letters Patent.

71 and both the rotor a Serial N0. 650,460.

tangential discharge or outlet at. of any other construction may be when the fan is simply used to exhaust the or compartment, may be dispensed with.

he rotating part or rotor B of the fan consists of a suitable frame or skeleton on which the blades or vanes, which propel the air, are mounted. The rotor, except for the shape and arrangement of the blades or vanes hereinafter described, may be of any suitable construction and rotatably mounted in any suitable way. As shown in the drawings, the frame of the rotor comprises a hub or spider b which is-rigidly secured to a shaft C, and a disk 6 secured to one end of the hub. The blades or vanes D are secured 'at one side thereof to the disk 6' an project laterally from said disk, the other side of the blades being connected and held in place by a .ring 6 The shaft C is journaled in any suitable way. A rotor frame of any other suitable construction may be employed and the blades may be secured to the frame by any suitable means. The fan blades or vanes D are longitudinally curved and taper from side to side, the larger sides of the blades being secured to the disk 6 and the smaller sides to the ring the inner and outer edges of the blades diverge from the axis of the fan in a direction away from the disk 6 so that the length or radial dimension of the blades increases from the inlet side, where the diameter of the rotor is greatest, toward the opposite side of the rotor, which is of smaller diameter, to obtain a relatively large air inlet with a relatively small rotor. The blades are preferably made as long as posy direction, in order to impart to the air the maximum trifugal force and thereby to increase the efficiency of the fan. In the operation of the fan the air enters the larger end of the central space surrounded by the blades through the inlet opening or eye a of the casing and is propelled outward by the blades As thus far described the rotor is tures now about to be described.

Each blade or vane of the fan is developed froma perfect conical surface. The dotted lines in Figs. 3 and t indicate the Patented May 41, 11%15.

cone completed and its position relative to the rotor. The axis of the cone is inclined both to an axial plane of the rotor and to a radial plane thereof. The curved edge cl of the blade, whichis secured to the disk I) of the rotor, is formed by a plane cutting the cone parallel to the disk I) and inclined to the axis of the cone, and the opposite curved edge at of the blade is formed by the intersection with the conical surface of another plane inclined not parallel with the plane forming the edge d. The heel or inner edge d of the blade is preferably substantially coplanar with the axis of the rotor while the tip or outer edge 3 is non-coplanar with the axis of the rotor, and neither the heel nor the tip of the blade is an element of the cone. By this formation and arrangement of the blades on the.

rotor they will cut the air entering the rotor in such a manner as to reduce to the minimum the shock caused by the impact of the air on the blades, and thereby materially increase the efficiency of the fan. The heel or inner edge d of each blade will cut the air at' an angle, which varies as the heel of the blade recedes from the axis of rotation. The acute angle, which is included between a tangent drawn to the surface of the blade at the heel thereof and a tangent drawn to the circle of revolution of the heel of the blade, will be greatest at the disk I), where the distance of the heel from the axis of rotation is least, and will gradually decrease toward the ring 5 where the distance from the axis is greatest. The difference in this angle at the opposite ends of the heel of the blade is represented in Fig. 3, in which e and e indicate the angles at the opposite ends of the heel of the blade. By forming the blades in this manner, those portions of the surface of theheel of the blade which are located at a greater distance from the axis of the rotor and therefore move at a greater peripheral speed, more nearly coincide with the direction of movement of the blade and thus change the direction of flow of the air at substantially the same rate as those portions of the heel of the blade located nearer to the axis and which move at a slower peripheral speed.

In a blade constructed as described, the angle at the heel of the blade is such as to cut the air at a properly varying angle with reference to the distance from the center of the rotor so that the loss by shock shall be at a minimum throughout the entire length of the blade. This loss by shock, which is thus practically eliminated, is the greatest obstacle to high efficiency. The air is discharged from the tip or outer edge of the blades at a uniform velocity and pressure throughout the width of the blades. This even discharge of air from the rotor also increases the efliciency of the fan. The correto the axis of the cone and even curvature and free spending angle 6 at the tip or outer edge of the blade is preferably made uniform throughout the width of the blade. The inlet end of the heel of the blade preferably extends inwardly beyond the edge of the inlet or eye a. of the casing. By laying the heel of the blade at a suitable angle to an element of the cone, the properly varying angle at the heel can be obtained. A blade developed from a cone surface can be easily made of from any undulations, such as indentations, flat or raised portions, which offer more or less resistance to the flow of air and thus decrease the efficiency of the fan. Another advantage in developing the blade from the cone surface is that a blade of this shape is easier to manufacture, making the blades can be easily made of the correct shape.

A fan provided with blades of the kind described has been found to be more efficient than multi-vane fans having scooped blades of other different formation, and the cost of manufacture is also decreased.

The fan shown in the drawings is of the single inlet type, but blades of the kind described can be used on fans of the double inlet type or with casings and rotors of other shapes.

I claim as my invention:

1. A centrifugal fan having a rotor provided with a plurality of propelling blades, the surface of each of the blades being a portion of the surface of a cone, substantially as set forth.

2. A centrifugal fan having a rotor provided with a plurality of propelling blades, the surface of each of the blades being a portion of the surface of a cone, and the inner and outer edges of the blades each at an inclination to elements of the cone, substantially as set forth.

3. A centrifugal fan having a rotor provided with a plurality of propelling blades, the surface of each blade being a portion of the surface of a cone, andthe axis of the surface of the blade being inclined to an axial plane of said rotor, substantially as set forth.

4. A centrifugal fan haidng a rotor provided with a plurality of propelling blades, the surface of each blade being a portion of the surface of a cone, and the axis of the surface of the blade bein. inclined to a since the dies or rolls employed in vided with a plurality of propelling blades, the surface of each blade being a portion of the surface of a cone, and the opposite sides of said blade lying in planes which are inclined toward each other, substantially as set forth.

7. A centrifugal fan having a rotor provided with a plurality of propelling blades, the surface of each blade being a portion of the surface of a cone, and the inner edge of each blade being substantially co-planar with the axis of the rotor, substantially as set forth.

' 8. A centrifugal fan having a rotor provided with a plurality of propelling blades, the surface of each blade being a portion of the surface of a cone, and the outer edge of each blade being non-coplanar with the axis of the rotor, substantially as set forth.

9. A centrifugal fan having a rotor provided with a propelling blades, each of the blades having a heel portion which is inclined with regard to the axis of the rotor, the portions of said heel which are located at a greater distance from the axis of the rotor more nearly coinciding with the direction ,of movement of the blade about the axis of the rotor than the portions thereof located at a shorter distance from the axis of the rotor, substantially as set forth.

10. A centrifugal fan having a rotor provided with a plurality of propelling blades, each of the blades having a heel portion which is inclined with regard to and substantially co-planar with the axis of the rotor, the portions of said heel which are located at a greater distance from the axis of the rotor more nearly coinciding with the direction of movement of the blade about the axis of the rotor than the portions thereof located at a shorter distance from the axis of the rotor, substantially as set forth.

11. A centrifugal fan having a rotor provided with a plurality of propelling blades, each of the blades having a heel portion which is inclined with regard to and substantially co-planar with the axis of the rotor, the portions of said heel which are located at a greater distance from the axis of the rotor more nearly coinciding with the direction of movement of the blade about the axis of the rotor than the portions thereof located at a shorter distance from the axis of the rotor, the outer edge of each blade being non-co-planar with the axis of the rotor, substantially as set forth.

12. A centrifugal fan having a rotor provided with a plurality of planar with the axis of the rotor, the p tions of said greater distance from the axis of the rotor more nearly coinciding with the direction of movement of the blade about the axis of the rotor than the portions thereof located at a shorter distance from the axis of the rotor, the outer edge of each blade being non-coplanar with said axis, substantially as set forth.

13. A centrifugal fan having a rotor provided with a plurality of propelling blades, the surface of each blade being a portion of the surface of a cone, the inner edge of of each blade being non-coplanar with said axis, substantially as set forth.

14. A centrifugal fan having a rotor provided with a plurality of propelling blades, the surface of each of the blades being a portion of the surface of a cone and each of the blades having a heel portion which is inclined with regard to the axis of the rotor and having the portions of the heel which are located at a greater distance from the axis of the rotor more nearly coincidin with the direction of movement of the blade about the axis of the rotor than the portions thereof located at a shorter distance from the axis of the rotor, substantially as set forth.

15. A centrifugal fan having a rotor provided with a plurality of propelling blades, the surface of each blade being a portion of the surface of a cone, and the heel of the blade extending at an angle to an element of the cone, substantially as set forth.

16. A centrifugal fan comprising, in combination, a volute-casing having an intake opening, a fan runner fitted within said casing and having its intake eye disposed adjacent to and opposite said opening, said fan runner comprising a plurality of scooped blades, the outer and inner longitudinal edges of which lie on substantially conical surfaces differently inclined to the axis of the runner, the outer cone being less inclined than the inner cone, both cones being truncated, the inner edge of each blade being coplanar with the axis of the fan runner, and the outer edge of each blade deviating from a plane rotating on the axis of the runner; means joining the inner ends of the blades, and means joining the outer ends of the blades, substantially as set forth.

1 A centrifugal fan bination, a volute casing having an intake opening, a fan runner fitted within said caslng and having its intake eye disposed adjacent to an opposite said opening, said fan surfaces differently e axis of the runner, the outer cone being less inclined than the inner cone, both cones being truncomprising, in com-v cated, the inner edge of each blade being co-planar with the axis of thevfan runner, and the outer edge of each blade deviating from a plane rotating on the axis of the runner, substantially as set forth.

18. A centrifugal fan comprising, in combination, a'volute casing havin an intake opening, a fan runner fitted within said casing and having its intake eye disposed adjacent to and opposite said opening, said fan runner comprising a plurality of tapered and scooped blades, the outer and inner longitudinal edges of which lie on substantially conical surfaces differently inclined to the axis of the runner, the outer cone being less inclined than the inner cone, both cones being truncated, the inner edge of each blade being co-planar With t e axis of the fan runner, and the outer e e of each blade deviating from a plane rotating on the axis of the runner; a disk joining the inner ends of said blades, and a ring joining the outer ends of said blades, substantially as set forth.

19. A fan runner comprising a plurality of tapered blades, the outer and inner longitudinal edges of which lie on substantially conical surfaces diiferently inclined to the axis of the runner, the external and internal diameter of the runner being greatest Where the blades are narrowest, the outer longitudinal edge of each blade deviating from a plane rotating on the axis of the runner, a

' ring joining the narrow ends of the blades, and a disk joining the wide ends of the blades, substantially as set forth.

20. A centrifugal fan runner comprising a plurality of scooped blades, the outer and inner longitudinal edges of which lie on substantially conical surfaces differently cone being less inclined than the inner cone, both cones being truncated, the inner edge of each blade being co-planar with the axis of the fan runner, and the outer edge of each blade deviating from on the axis of the runner, and means joinlng the Wide ends of the blades, substantially as set forth.

21. A centrifugal fan runner comprising a plurality of blades,

surfaces difierently inclined to the axis of the runner, the outer cone being less inclined than the inner cone,both cones being truncated, the inner edge of each blade being co-planar with the axis of the fan runner, and the outer edge of each blade deviating from a plane rotating on the axis of the runner, substantially as set forth.

22. A centrifugal fan runner comprising a plurality of tapered and scooped blades, the outer and inner longitudinal edges of which lie on substantially conical surfaces differently inclined to the axis of the runner, the outer cone being less inclined than the inner cone, both cones being truncated, the inner edge of each blade being co-planar with the axis of the fan runner, and the outer edge of each blade deviating from a plane rotating'on the axis of the runner; a disk joining the Wide ends of said blades, and a ring joining the narrow ends of said blades, substantially as set forth.

Witness my'hand this 19th day of September, 1911.

WILLIS H. CARRIER.

Witnesses:

F. E. PRoEHNow, A. L. MCGEE. v

the outer and inner lon-- gitudinal edges of which lie on substantially conical clined to the axis of the runner, the outer a plane rotating 

